Crown sheave support for drilling machines



Oct. 22. 19 0- H. o. WILLIAMS m AL CROWN SHEAVE SUPPQRT FOR DRILLING MACHINES Filed Jan. 22, 1938 3 Sheets-Sheet l 1| HHI I lllmrlllll Fiji 0st, 22, 1940. H. 0. WILLIAMS ET Al. 292199051 CRQHN SHEAVE SUPPORT FOR DRILLING MACHINES ct- 22. 1 H. o. WELLXAMS ET AL I 2,219,961

CROWN SHEAVE SUPPORT FOR DRILLING MACHINES Filed Jan. 22, 1938 3 Sheets-Sheet 3 Inventor's H. O. WLLLLams.

WC K; 5 ttor eg- Patented Oct. 22, 1940 UNITED STATES PATENT OFFICE CROWN SHEAVE' SUPPORT FOR DRILLING MACHI NES Application January 22, 1938, Serial No. 186,378

9 Claims.-

Our invention relates to crown sheave supports for drilling machines, and has for itsobject to provide a shock-absorbing member which will receive and absorb the action of the drilling machine in reciprocating the drilling tool.

In drilling machines of this type a heavy tool, usually weighing from one thousand to three thousand pounds and in certain cases much heavier, hangs vertically from the end of a cable which passes over what is called the crown sheave to a sheave on a walking beam operated by a crank from a large fly wheel. The beam lifts the tool and it falls by gravity and at the moment of impact the beam again lifts the tool, 15 with the result that very heavy shock strains are imposed on the crown sheave.

It is an object of our invention to provide a specially constructed shock absorber for taking up these shock strains wherein a shock-absorbing 20 cylinder is provided embodying a multiplicity of independent discs each supporting a multiplicity of resilient buffer members distributed uniformly between the plates withmeans for passing air through said plates and into and out of the 25 cylinder.

It is a further object of our invention to provide a cylinder as above indicated which is substantially air-tight and yet which has valve mechanism provided for admitting air when the 30 resilient members are compressed and permitting air to escape from the cylinder when the resilient members rebound.

It is a further object of our invention to support the crown sheave directly upon the aforesaid 35 resilient members within the cylinder by means of a sheave support vertically slidable and an intermediate cylinder connector or piston.

It is a further object of our invention to arrange the parts in reverse order so that the crown 4o sheave will be below the shock absorber.

It is a further object of our invention to provide a sliding block in which the crown sheave is journaled and to support this block upon a piston operative within a cylinder, and to provide means 45 upon which the piston operates having air-tight engagement with the walls of the cylinder and supported directly by resilient members within the cylinder.

It is a further object of our invention'to pro- 50 vide a particularly strong compact and effective frame support for the crown sheave holding members and the shock absorber connected therewith.

The full objects and advantages of our inven- 55 tion will appear in connection with the detailed description thereof, and its novel features are particularly pointed out in the claims.

In the drawings, illustrating an application of our invention in one form- Fig. 1 illustrates in vertical elevation the crown sheave and shock absorbing support therefor positioned at the end of a derrick of standard construction with the crown sheave above the shock absorber. Fig. 2 is a transverse section of a construction wherein the crown sheave is below its support and shock absorber. Fig. 3 is an edge elevation view of the parts with some portions broken away and in section. Fig. 4 is a sectional elevation view taken on line 44 of Fig. 1. Fig. 5 is a sectional plan View taken on line 5-5 of Fig. 4. Fig. 6 is a sectional plan view taken on line 6-6 of Fig. 4. Fig. 7' is a sectional plan view taken on line l-'! of Fig.4 and Viewed upwardly as indicated by the arrows. Fig. 8 is a sectional plan view taken on line 8-8 of Fig. 4. Fig. 9 is a sectional plan view taken on line 9--9 of Fig. 4. Fig. 10 shows one of the discs with an arrangement of resilient bufiers in different form from what is shown in Fig. 8. Fig. 11 is a side elevation view of one of the cylindrical buffers.

To the ends H] of a derrick of usual construction are secured by bolts ll, I2 a pair of channel members l3 and M which constitute the supporting framework for the crown sheave IS. A carrier l6 of the general shape shown in Figs. 4 and 5 is formed of channel members I1 and i8, Fig. 5, having winged fiangesiS. 2D and 2|, 22. Each of the members I! and I8 has a wood backing formed of pieces 23, 24 and 25 which pieces have sliding contact within the channel frame members l3 and I4. Welded to the members ll and I8 are tubular bosses 23 and 21, Figs. 3 and 4, and secured to these bosses by bolts 28 and 29 is a spindle or connector shaft 30 by which the channel members I! and I8 are held together at the top, a base member 3| being secured to channel members I1 and I8 at its bottom. Upon a bearing member 32 on spindle 30 is rotatably mounted the crown sheave l5, and a pilot shaft 33 is secured at the center of bottom plate 3|. A cable 34 passes over 'crown sheave I5 and to it is secured the tool 35. The other end of cable 34 passes around the spudding sheave 36 on the walking beam 31 operated in a customary manner by crank 38 and connector link 39. 50

As clearly shown in Figs. 4 and 9, a circular supporting partition 40 is welded to derrick ends I0. Resting upon this supporting member 40 is a base 4| of a cylindrical member 42 open at its top as shown at 43 in Fig. 4. The bolts 1 l and I2 55 r the several plates.

which secure the supporting channels l3 and Hi to the upper derrick ends Ill also secure the cupshaped cylindrical member 42 in position with its base M in engagement with the supporting partition 40. Spacer strips 44, Figs. 2, 3 and 8, hold the cylindrical walls 42 away from the inner walls of derrick channels I0 so as to leave a suitable space 45 down which slides the cylindrical walls 46 of a dust cap 41 which rests (in Fig. 4 it is shown integral with) on a cylindrical piston 48 having its top 43 formed at its center with a cylindrical hole 55 in alinement with'a corresponding hole 51 in bottom plate 3|, and the pilot shaft 33 of the carrier member l6 extends through the openings and 5! forming a bottom guide for said carrier member. f

The piston 48 is provided with a bottom wall 52 which carries at its center a ball check valve construction 53 adapted to close and open an aperture 54 at the bottom of said Valve structure,

Below the bottom wall 52 is a closure member 55 which engages the inner walls of cylindrical member 42 in a substantially air-tight manner and which is provided with a central aperture 56 in alinement with aperture'54 in the check Valve structure 53.

The supporting plate 40 and bottom member 41 are provided with central apertures under which is mounted ball check valve structure 51. As clearly shown in Fig. l, the check valve member 53 closes for downward movement of air and opens for upward movement of air, while the check valve 51 closes for downward movement of air an dopens for upward movement of air, all for a purpose to be hereinafter described. The plate ll, as clearly shown in Fig. 9, has a series of grooves 5la. adapted to receive air from the check valve structure 51 and distribute it in a manner hereinafter described.

Within the cylinder cup 42 are positioned a multiplicity of disc-like plates 59, as best shown in Fig. 8. Each plate is formed with two series of holes, 55 for centering and holding the resilient shock absorber members hereinafter described, and 5t for permitting free flow of air through The first of these plates 59 rests upon the bottom wall 4| of the cup member 52 and upon it are fixed a series of resilient cylinders 52, preferably formed of resilient and suitably compressible rubber, the distribution of these cylinders for a given plate being shown by the dotted-line circles of Fig. 8. Each succeeding plate 59 carries its quota of compressible cylinder blocks 52 and a structure is built up, as clearly shown in Figs. 3 and 4, which comprises a multiplicity of sets of plates 59 and intervening resilient blocks 62. As shown inFig. 3, there are twelve such sets of plates and rubber blocks, but obviously the number may be varied in accordance with the requirements to be met in the use of any particular well drill. Upon the top plate 59 rests a supplemental plate 53, which is shown in plan in Fig. 7. The plate 63 is provided with a multiplicity of grooves 54 all leading to a central aperture 65 in plate 53, which, in turn, communicates through apertures 54 and 56 with ball check valve structure 53, This ball check valve structure, as

shown in Fig, 6, is at the bottom of a small sup- 55 between the wall 48 a-nd the dust cap wall 4.6

and to escape below the lower edge of the dust cap wall.

As shown in Fig. 10, resilient members 10 and H of a curved trapezoidal shape may be employed to rest upon plate 59 in place of the cylindrical members 62.

In the form of the device shown in Fig. 2 the crown sheave support I6 is shown mounted below the members described in the-form shown in Figs. 4 and 5. In this form of the device a top plate 12 is shown connected at 13 with a yoke hanger 14 which overlies at 15 the cylindrical follower piston 48 with a pilot bolt or shaft 76 extending through the aperture 50 in the top plate 49 of said follower 48. The dust cap 46 and all other parts of this construction including the cupshaped cylinder member 42 are otherwise similar in structure and operation to the similar parts of Fig. 5 in which the crown sheave is above the shock absorber. In each of these forms the method of operation is the same, This operation is as follows:

The force of the blow upon the crown sheave when the walking beam 31 starts to lift the heavy tool 35 is transmitted through sliding of the carrier H3 in the frame members I3, [4 to the cylindrical piston 48 and through that to the assemblage of plates 59 and resilient buffer members 62. These members will all be compressed under the force of the blow and the space within the cylinder 42 will be contracted. Under these conditions the air in cylinder 42 will escape through this contracted space past the ball check valve structure 53 and out of openings BI and 68 to outside atmosphere. The movement of air from all parts within the cylinder is made effective by reason of the vent holes in the plates 59, and the air further readily reaches the discharge port by reason of the series of channels 66 in mem: ber 63 as shown in Fig. 7. The compression of buffer members 62 will be uniformly distributed among all of the several plates 59 because of the arrangement of these buffers upon said plates, as clearly shown in dotted lines in Fig. 8. It will be noted from Fig. 8 that the apertures 60 in the plates 59 are symmetrically disposed and receive plug extensions 11 formed at the centers of the buffer members 62 whereby these members at all times are held in the symmetrically distributed arrangement of Fig. 8. When the compressed bufier plugs react in the opposite direction to expand both from normal reaction from over-compression and upon the release of the tool, the chamber within cylinder 42 will correspondingly expand and air will pass the ball check valve structure 5'! to fill the expanded chamber, the passage of this air. being facilitated by the numerous vent holes 60 in the plates 59 and by the channels 58 formed in the plate 4| leading to the outlet from the ball check valve structure 51.

It will be noted that the above-defined instrumentalities will have the effect of thoroughly ventilating the chamber within cylinder 42 including the buffer members, fresh air being drawn in and other air being passed out. This is of high importance in many cases, particularly in warm weather, since the rapid compression and expansion of the buffer members 62 produce a great deal of internal heat. This heat is effectively removed by the ventilating means above described.

wrench. The cone valve constructionjis such that the amount of air which can pass the ball check valve structure 53 may be varied from none at all up to the maximum amount requisite. It will be noted that there will always be some compression of air withincylinder chamber 42 which furnishes additional cushioning means to take up the blows on the crown sheave. And the amount of such cushioning will vary in proportion to the degree of opening of the release valve 18. This is true because the edges of closure 55 make airtight engagement with the inner surface of cylinder member 42. The result is that when the resilient members, specifically the rubber plugs 62 on plates 59, are compressed from the efiect of a blow transmitted from the sliding blocks supporting the crown sheave, the air within cylinder 42 will be compressed, thus additionally cushioning and absorbing the shock of the blow. In the event that the release valve i8 is entirely closed there will be complete compression of all air within cylinder 42. To the extent that there may be leakage about the edges of closure disc 55, such air will be replaced in the chamber within cylinder 42 when the parts react to restore themselves to initial position by influx of air through the check Valve structure 51, In many cases such an arrangement closing off all escape of air through ball check valve structure 53 will be superior in its operative result to the one heretofore described in which some part of the air within cylinder 42 is permitted to escape through check valve structure 53. v

The advantages of our invention have quite clearly appeared from the foregoing description. The use of buffer members in a closed cylinder with valve means for inlet of air provides a shock absorber system of the highest efiiciency. The air itself, compressed to some extent at the time of the impact of the blow from the tool upon the crown sheave, even when the outlet valve is used, aifords a cushioning eiTect, which, added to the compressibility of the very large number of resilient buffer members, provides a highly efiective shock absorber for the purpose. Indeed, under certain conditions the device might be constructed to function without any air inlet or outlet. However, the arrangement of valved air inlet as above noted, has the eiTect of permitting requisite ,air cushioning at the moment of severest impact from the blow on the crown sheave and subsequent inlet of air to keep the buffer members 62 in their most efiective condition.

We claim:

1. A well drill comprising a derrick, a block mounted for sliding movements along said derrick, a crown sheave journaled in said block, a support for said block comprising a closed cylinder and a piston movable therein, resilient means in said cylinder and subject to the action of the piston for absorbing the shock of blows upon the crown sheave, and check valves in said piston and below said piston for permitting air to escape from said cylinder and to enter said cylinder.

2. A well drill comprising a derrick, a crown sheave mounted for sliding movements along said derrick, a support for said crown sheave mounting including a closed cylinder, a multiplicity of discs within said cylinder, said discs being provided with a symmetrical arrangement of holes, and a multiplicity of bufiers on each disc and holding said discs spaced one from the other, said buffers being provided with lug extensions seated in said holes to hold the several bufiers in position on the discs.

3. A well drill comprising a derrick, a crown sheave mountedfor sliding movements along said derrick, a support for said crown sheave mounting including, a closed cylinder, a multiplicity of discs within said cylinder, said discs being, provided with a multiplicity of symmetrically arranged holes, and a corresponding number of cylinders of resilient material such as rubber on said discs, said'cylindersof resilient material having lug extensions seated in said holes to hold the bulfers in position.

4. A well drill comprising a derrick, a crown sheave mounted for sliding movement along said derrick, a support for said crown sheave mounting including a closed cylinder, resilient means in said cylinder for absorbing the shock of blows upon the crown sheave, means for admitting air to said cylinder, means for releasing air from said cylinder, and means for causing the air to be distributed throughout the cylinder and about the resilient means for ventilating the cylinder and cooling the resilient means.

5. A well drill comprising a derrick, a crown sheave mounted for sliding movements along said derrick, a support for said crown sheave mounting including a closed cylinder, a multiplicity of discs Within said cylinder, a multiplicity of resilient bufier members positioned between each pair of discs and spaced so as to be out of contact with each other, said bufier members receiving and absorbing the shock of the blows transmitted, and means for effecting a circulation of air to and from the spaces about said buffer members.

6. A well drill comprising a derrick, a crown sheave mounted for sliding movements along said derrick, a support for said crown sheave mounting including a closed cylinder, a multiplicity of discs within said cylinder, a multiplicity of resilient buffer members positioned between each pair of discs and spaced so as to be out of contact with each other, said buifer members receiving and absorbing the shock of the blows transmitted, means forefiecting a circulation of air to and from the spaces about said buffer members, and means for regulating the Volume of flow of said air.

7. A well drill comprising a derrick embodying spaced channel members, a block and crown sheave slidable along said channel members, a cylinder and resilient means in said cylinder, a piston having top and bottom walls, said bottom wall being supported by said resilient means, the block resting upon the topwall, and a depending pilot shaft extending through an aperture in the top of the piston, whereby the block and piston are held in alignment and the resilient means is adapted to absorb shock of blows upon the crown sheave through the block and piston.

8. A well drill comprising a derrick, a block and crown sheave carried thereby mounted for sliding movements along said derrick, a support for said block including a cylinder with a bottom wall having means for admitting air therethrough to its interior, a multiplicity of disks within said cylinder, a symmetrical arrangement of separated resilient buffers held on each of said disks and holding said disks spaced one from the other, means at the top of the cylinder for permitting air to leave the cylinder, and a multiplicity of holes in each of said disks opening into spaces between the disks outside the limits of said buffers to cause the air entering and leaving the cylinder to circulate about the bufiers.

cylinder and held spaced from the upper edge thereof for keeping out dust and rain,- said closure formed with cylindrical Walls surrounding the upper part of the cylinder and spaced therefrom to allow air which leaves the cylinder at the top 5 to move outside past the edges of said closure.

HOWARD O. WILLIAMS. WESLEY C. KEYS. 

